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HSL Rapid Response Laboratories

The HSL Pathology Service comprises core laboratories, which are the centralised services based in the Halo Building, Central London, and four Rapid Response Laboratories based locally, serving University College London Hospitals, Royal Free London Hospital, Barnet and Chase Farm Hospitals, and the North Middlesex University Hospital.



UCLH Rapid Response Laboratory (RRL)

60 Whitfield Street, London W1T 4EU

HSL UCLH RRL is a UKAS Accredited Medical Laboratory No. 10204.

Royal Free London Rapid Response Laboratory (RRL)

Pond Street, London NW3 2QG

HSL RFH RRL is a UKAS Accredited Medical Laboratory No. 8793.

North Middlesex University Hospital Rapid Response Laboratory (RRL)

Level T0, Main Building North Middlesex Hospital Sterling Way, Edmonton London, N18 1QX.

HSL NMUH RRL is a UKAS Accredited Medical Laboratory No. 9354.

Barnet General Hospital Rapid Response Laboratory (RRL)

(also serves Chase Farm Hospital) Level 3, Wellhouse Lane, Barnet Herts EN5 3DJ.

HSL BCF RRL is a UKAS Accredited Medical Laboratory No. 8359.

Opening times

All RRLs operate a 24/7 service for Specimen Reception, Chemistry, Haematology and Blood Transfusion.

Normal working hours are considered to be 09:00 – 20:00 Monday – Friday.

Out of hours are considered to be 20:00 – 09:00 Monday – Friday and weekends/public holidays. During these periods, a reduced staff complement is present in all sections. Priority is given to urgent and emergency cases.

Out of hours

Contacting the laboratories out of hours:

Royal Free: 020 7794 0500 bleep 71-1595

Barnet Chase Farm: 020 8216 4600 extension 65037

North Middlesex: 020 8887 2263 / 2670

University College London Hospitals: 020 3447 9405